Subterranean deposits of coal contain substantial quantities of entrained methane gas limited in production in use of methane gas from coal deposits has occurred for many years. Substantial obstacles, however, have frustrated more extensive development and use of methane gas deposits in coal seams. Dual well systems have been used to aid in producing the methane gas from the coal seams. Such dual well systems may include two wellbores that intersect at a junction. In particular cases, an enlarged, cylindrical cavity is formed at a proposed junction to act as a target for the intersection of the wellbores.